Pneumatic canopy



March 30 1948. c. s. HULTON 2,438,606

PNEUMATI C CANOPY Filed March 16, 1944' IN VEN TOR. (bar/es 6. flulz'an Patented Mar. 30, 1948 PNEUMATIC CANOPY Charles S. Hulton, CincinnatL'OhiO, assignor to The Kirk & Blum Manufacturing Company, Cincinnati, Ohio, a corporation of Ohio Application March 16, 1944, Serial No. 526,801

7 Claims.

The present invention relates to a canopy or hood for use with industrial installations such as foundry shake-outs which in operation, release air-borne substances that must be removed, and particularly to industrial installations of this class that have presented difficulties due to the method of handling large objects to be, operated upon.

An object of the invention is to provide a simple and inexpensive canopy structure that is readily deformable and self-righting so that the canopy offers no serious impediment to the'handling of materials or objects by means of a crane hoist. Another object of the invention is to provide a pneumatic canopy which in use projects over a source of air-borne substances in order to enhance the effectiveness of the air exhauster apparatus employed for controlling the released substances. Still another object is to provide a flexible inflated canopy for the indicated purposes which canopy is arranged to facilitate movement of work or material to and from the site of operation while suspending from the chains or cables of a crane hoist.

A still further object of the invention is to provide a pneumatic hood structure which in operation serves to maintain an air pressure area beneath it for retarding the rate of rise of re leased air-borne substances and thereby subjecting such substances to the operation of the existing air exhauster type collecting means with greatly increased efiiciency.

These and other objects are attained by the means described herein and disclosed in the accompanying drawings in which:

1 is a side elevational view of a foundry shake-out including an air exhauster-apparatus having a pneumatic canopy of the invention mounted thereon.

Fig. 2 is a top plan view of the View of'the device of Fig. 1.

Fig. 3 is an enlarged cross sectional view taken on line 33 of Fig. 2. v

Fig. 4 is a front elevational view of a foundry shake-out installation having modified form of the pneumatic canopy of the invention associated therewith.

Fig. 5 is a cross sectional View taken on line 55 of Fig. 4.

It is known in the industrial arts to remove dust, smoke, gases and any other air-borne substances for the purpose of protecting workers, or collecting air-borne substances and for maintaining an atmosphere free of the various air-borne substances. The well-known foundry shake-out is an example of an industrial installation which,

in its operation of freeing the foundry flasks of their finished burden, releases dust, gases. and smoke, the control of which has been efiected to some degree by air exhauster type apparatus disposed alongside the shake-out grate. In those instances where the work is moved to and from By the present invention the previous difiiizul- I ties are substantially overcome so that the with-. drawal of air-borne substances from the atmosphere in the immediate vicinity of their release is made more complete and is effected at greatly reduced power costs. The present invention consists essentially in disposing above the shake-out grate or point of release of air-borne substances, a canopy that is flexible but self-sustaining, so that it will yield readily in the event of collision of the crane hoist chains or theburden without derogatory effect on the canopy structure. The invention consists further in providing such, a

flexible canopy structure with a means for discharging air streams in opposition to the normal stack draft conditions of the room and to thus afford a sort of air blanket which confines the substances to be removed to the relatively restricted space in which air exhauster type removal apparatus is most effective.

, Referring now to the drawings, it will be noted in Fig. 1 that the casing I0 forms part of an exhausting'device such'as a dust collector apparatus and shake-out II is disposed immediately alongside the shake-out. Shake-out H has agrate l2 across which air is caused to travel at a suitable velocity through controlled openings in a battle it into an equalizing plenum chamber It from whence the air is exhausted at a suflicient rate by any suitable means. In applying the canopy of the present invention to the hereinbefore referred to exhausting structure, it is necessary only to provide a simple air pressure chamber 15- which consists of a rigid box-like structure disposed atop of the casing It A suitable low capacity blower or fan structure I6 is arranged to provide a relatively constant volume of pressure air to the chamber l5, the air intake being in this case supplied through pipe ll which may communicate with the exterior of the building. Chamber I5 is provided on its forward vertical side by a suitable surrounding flange l8. The flange |8 receives the mouth of a large flexible envelope constituting the body of canopy l9 which may be of canvas or other more fireresistant fabric such as the asbestos and glass fiber fabrics now known and available in the markets. The mouth of envelope I9 is rectangular to snugly fit flange l8 and a binding strap 20 serves to secure the mouth of the envelope over the open side of pressure chamber I5. In its preferred form the envelope comprising canopy I9 is formed at its forward edge into a plue. rality of hollow tubular fingers 2|. In. order to, sustain the rearward portion of the envelope against undue bulging, the top and bottom walls of the envelope are connected by fabric strips or gussets 22 which are aligned with the junctions of the fingers 2| (see Fig. 3). Upon inflation 'of the envelope the adjacent fingers assume sub-1 stantial, contact withqeach other and the rear portion of the envelope assumes a wide flattened. shape, the thickness of, which is substantially limited by the interiorly connected fabric gussets. In the forward lower portion ofeachof the fingers 2| there is provided at least one restricted port or opening 23.which may be suitably reins forced by a grommet 24. V

In .use,.the air exhauster apparatus is set into operation for creatinga velocity air flow in the direction, of the arrows 25 and passing through the equalizing plenum chamber l4 and in the direction of. arrow 26 through pipe 21. With blower apparatus IS in operation the, envelope 22 becomes inflated and assumes the substantially horizontal position as shown in Figs. 1, 2, and 3, an d alsodischarges streams of air indicated at .28 inc. downwardly direction beneath the hood. The efiect' of air streams 28 is to oppose the normally upward movement of air and itsets up a blanket of pressure, air in opposition to the natural tendency of the heat,

4. generally to the casing ll) of Fig. 1, has mounted on the upper portion thereof .an inverted substantially U-shaped pressure chamber 32 with a suitably driven fan or blower I69 mounted on the top thereof. The canopy I99 has its rear edge secured in open communication with the U-shaped outlet side of chamber 32 in any suitable manner, for example as described in con- Canopy I90 canopy .structure is preferably provided with tubular fingers 34 on. the forward edge thereof. As is best ;illustrated in Fig. 4, the depending side walls 33 assist'in confining an area above the shake-out II. An intake chamber 35 is in- I terposed between casing Hi9 and the pressure chamber 32 so that the intake port 36 is disposeddirectly beneath the canopy. By means of this structure there is attained a recirculation of air which is utilized to keep the canopy'infiated and in a self sustaining position. The flow of velocity air which passes through the ports in 7 baffle I30 is taken intothe' equalizing plenum chamber 149 and thence through pipe 2'||l.' In

operation the'blower I80 produces the desired volume of pressure' air to inflatethe envelope comprising the canopy I90 and the downwardly directed streams of' pressure airfr'om the open-v ings 230 maintain a pressure air body'around the Work such as flasks 30 in order to' oppose the spread of liberated dust, smoke and the like to the surrounding atmosphere. 'It'will be 7 further understood that the air streams fromv ports 23!] also tend to set 'up a flow of air fromthe surrounding atmosphere inwardly through the'spaces between the fingers 34.

It will .be'unde'rstood that the recirculation of i the inflating pressure air is effected at a somedust andpsmokegto rise from the shake-out. This not-only prevents the dust, smoke and the like I from escaping into the free atmosphere, but

tends. to increase the efiectiven ess of the air stream 25 "soth at considerably lesser power costs are involved in maintaining a suificient velocity of the air stream 25 to collect the released airborne'substancesfrom the vicinity of the shakeout grate. It is to be understood that the capacity of fan or blower apparatus l6 need not be great 'inorder to maintain a sufflcient air pres sure within the envelope l9 to sustain the latter in the outstretched condition as shown. The canopy l9 may be extended to and beyond'the center of the surface of grate l2 so that should the cable or' chain 29 which supports the flasks 30 in moving'the'latter to and from the grate may encounter the canopywithout injury to the latter. The spaces 3| between adjacent fingers 2| of the canopy provide for the passage of cable or-chain 29 without'any' deformation whatso ever of the canopy." Likewise should one of such fingers 2| be collapsed by the cable during entry of the burden to the grate, then'the shifting of the cable will enable the pneumatic finger 2| to readjust itself to substantially normal out stretched position,

When the shake-out apparatus is shut down and'out of use, the canopy l9 would be deflated because fan l6 would be at rest and the canopy' from the exterior of abuilding for example as by pipe IT as shown in Fig. 1. At least a proportionate increase in efliciency of-the air ex-. hauster apparatus I00 is gained by the cooperative relationship of the parts'as shown inFig. 5.

It will be understood that the use of the depending side walls *33'may be eliminated if desired in a construction as typified in Figs. 4 and 5, and that a structure as exemplified inFigs. l and 2 may be modified within the scope of this invention, by the addition of such canopy side walls. Y

In general the costs involved intheconstruc tion of a canopy'of a' class'herein described and c the work may be brought to and removed from the shake-out because the danger ofda'mage to the canopy is completely eliminated. I

It will be understood that the envelope l9 forming the canopy may be constructed completely ofindividual cylindrical finger members secured directly to a pressure chamber l5, such a construction serving to afford a somewhat greater degree of flexibility to the structure in. use. Such an arrangementof independent cy-' lindrical fingers in side by side relation throughdue tosomeunusual occurrence. r

What is claimed is:

'1. In an air 'exhaus ter type collection appara? tus the combination of a casing having an intake opening in a vertical side wall thereof, means connected with the casing for drawing in air and dust through said opening, an air pressure supply chamber mounted on the casing and having an outlet in a vertical plane disposed above said inlet opening in said casing and a flexible inflatable envelope connected at its rear edge with the air pressure chamber and communicating interiorly with the air outlet in said chamber, and means supplying pressure air to said chamber, whereby the envelope is maintained in an inflated condition and extends horizontally to form a canopy over a substantial area adjacent and communicating with said intake opening in the casing.

2. A canopy of the class described comprising side by side tubular portions each closed at a common end and open on the opposite end, a relatively flat hollow flexible fabric body secured to and in open communication with the open ends of said tubular portions, each being in substantial contact with adjacent tubular portions and said tubular portions having restricted vent ports in the bottoms thereof, means for securing said body to a vertical side wall and means for continuously supplying air under pressure to said envelope for filling the envelope and yieldably projecting in a horizontally extended relation to the supporting side wall.

3. In a self-positioning canopy structure, the combination of a flexible fabric envelope having one open edge and the remaining edges closed, means for securing said open edge to a vertical Wall and means for constantly introducing air under pressure into the opened and attached edge of the envelope for maintaining said envelope in a pressure filled distended and horizontally extending condition.

4. A foundry shake-out installation comprising a shake-out including a grate, air exhauster type collecting apparatus including a casing disposed in upright position alongside said shakeout end having an inlet opening on the side adjacent said shake-out, a flexible hollow envelope rigidly secured horizontally along one side thereof to said casing above said inlet opening and means for supplying pressure air into said en- Velope at its said rigidly secured side whereby said envelope is inflated and distended and yieldably maintains a projecting position overhanging a substantial area of the grate.

5. In an air exhauster type collection apparatus the combination of a casing including a vertical side wall having an intake opening therein and defining one side of an extended work area requiring substantially unimpeded access from its remaining sides, means connected with the easing for drawing in air and dust through said opening, an air pressure supply chamber mounted on top of the casing and substantially within the body lines thereof, said chamber having an independent, transverse air'pressure outlet closely above the top of said intake opening in the casing, a flexible fabric, flat envelope of width corresponding to the width of the work area and of length corresponding to a substantial portion of the length of said work area, said envelope having an opening along its rear edge, means securing the sides of said opening about the air pressure outlet in said chamber for establishing communication with the interior of the envelope, means providing a pressure air supply to said chamber and flexible means secured at opposite edges to the interior top and bottom of the envelope for limiting the distention of the envelope in the direction of its thickness only under the influence of said pressure air whereby said envelope under continuous air pressure assumes a self-sustaining, horizontal roof-like position over a substantial portion of the work area adjacent the casing.

6. In an air 'exhauster type collection apparatus the combination of a casing including a vertical side Wall having a suction intake opening therein, means connected with the casing for drawing in air and dust through said opening, an air pressure supply chamber mounted on the casing and having a transverse pressure outlet opening at leastco-extnsive with said collection intake opening in the casing and in substantially the same plane therewith, a substantially fiat, flexible fabric envelope having an opening at its rear edge only, means securing the envelope to said pressure supply chamber with the opening in the envelope communicating with the opening in said chamber, said envelope being of substantial length and breadth, flexible members connected at their opposite ends to the opposed, inner major faces of the envelope for limiting separation thereof, and means providing a constant supply of pressure air to said chamber for maintaining the envelope in a distended, flattened and substantially horizontal, roof-like position above the top of said intake opening in the casing and over a substantial portion of the area immediately adjacent whereby airborne substances released in said work area are substantially precluded from movement out of the zone of suction of said intake opening.

7. A canopy of the class described comprising a relatively fiat hollow flexible body, means to rigidly mount the rear edge of said body on a vertical supporting surface, means to introduce air under pressure into said hollow body at said rear edge for inflating said body and pneumatically sustaining it at substantially right angles to the vertical supporting surface, a series of integral tubular fingers extending outwardly from the forward edge of said body, said fingers being closed at their free ends and individually in communication with the interior of the body at the forward edge of said body, said fingers each contacting adjacent fingers whereby said fingers form a composite and sectionally deformable forward extension on said body, and gusset members secured in spaced relation across the interior of said body and limiting the expansion thereof under pneumatic pressure to substantial conformity with the series of hollow fingers.

CHARLES S. HULTON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 67,894 Marshall Aug. 20, 1867 461,712 Putnam Oct. 20, 1891 1,392,870 Fessler Oct. 4, '1921 1,969,953 Swartz Aug. 14, 1934 2,074,317 Allan et al Mar. 23, 1937 2,134,588 Stacey, Jr. Oct. 25, 1938 2,214,821 Lucius Sept. 17, 1940 2,239,572 Richa Apr. 22, 1941 2,240,857 Pitner May 6, 1941 2,292,665 Schneible Aug. 11, 1942 2,355,248 Stevens, Jr. Aug. 8, 1944 

